42 lines
920 B
Markdown
42 lines
920 B
Markdown
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# JSON_USE_IMPLICIT_CONVERSIONS
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```cpp
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#define JSON_USE_IMPLICIT_CONVERSIONS /* value */
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```
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When defined to `0`, implicit conversions are switched off. By default, implicit conversions are switched on.
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Implicit conversions can also be controlled with the CMake option `JSON_ImplicitConversions` (`ON` by default) which
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sets `JSON_USE_IMPLICIT_CONVERSIONS` accordingly.
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## Default definition
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By default, implicit conversions are enabled
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```cpp
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#define JSON_USE_IMPLICIT_CONVERSIONS 1
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```
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## Examples
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??? example
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This is an example for an implicit conversion:
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```cpp
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json j = "Hello, world!";
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std::string s = j;
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```
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When `JSON_USE_IMPLICIT_CONVERSIONS` is defined to `0`, the code above does no longer compile. Instead, it must be
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written like this:
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```cpp
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json j = "Hello, world!";
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auto s = j.get<std::string>();
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```
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## Version history
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- Added in version 3.9.0.
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